This invention relates to a flexible damped bearing and, in particular, to a sealing arrangement for maintaining a high pressure squeeze film acting between a movable bearing support and a stationary component.
In U.S. Pat. No. 3,456,992, to Kulina, a flexible damped bearing is disclosed wherein the bearing is housed within a movable member and the member suspended from a stationary frame upon circumferentially spaced flexure springs. The springs are tuned to provide the bearing assembly with a predetermined mechanical stiffness capable of attenuating the harmful effects of shaft vibrations. To further enhance the bearing's response, a fluid squeeze film is formed about the movable member which acts against the stationary frame and thus serves to dampen the bearing's reaction to shaft induced vibrations. As disclosed by Kulina, seals are maintained within the damping cavity to contain the high pressure damping fluid therein. The seals are adapted to ride against the side walls of the cavity and thus add friction or coulomb damping to the system. Because two separate and distinct damping mechanisms are involved, the design of the damping system, particularly where the bearing must react in a prescribed manner over a wide range of frequencies, becomes relatively complex. Furthermore, when this type of mechanical or friction damping is present, the seals become worn with usage thus producing an unwanted change in the damping characteristics of the system.